Effect of needle length on incidence of local reactions to routine immunisation in infants aged 4 months: randomised controlled trial

Using longer needles to immunise infants causes less redness, swelling and tenderness, according to research in this week's BMJ. The study calls for vaccine manufacturers to review their policy of supplying a shorter needle in vaccine packs.

Researchers in Oxford recruited 119 healthy infants, aged four months old, attending routine immunisation clinics. Infants were randomly immunised either with a 25 gauge, 16mm needle or a 23 gauge, 25mm needle - both commonly used in general practice. Local reactions, such as redness, swelling and tenderness were recorded for three days after immunisation.

The authors found that both redness and swelling were significantly reduced when the longer needle was used. Rate of redness with the longer needle was initially two thirds the rate with the smaller needle, and by the third day this had decreased further to a seventh. Rate of swelling with the longer needle was initially about a third that with the smaller needle, and this difference remained for all three days. The overall local reaction rate was 62% for the longer needle, compared to 84% for the shorter needle.

Any factor that can reduce the rates of adverse reactions in childhood vaccinations has the potential to improve parental acceptance of vaccines and would be welcomed by practitioners, say the authors. They call on vaccine manufacturers to supply longer needles for routine vaccinations in the UK.

Contact:

Linda Diggle, Senior Research Nurse, Oxford Vaccine Group, John Radcliffe Hospital, Oxford, UK
Email: [email protected]